1. Field of Invention
The present invention generally relates to a system for connecting two vehicles in gaseous flow communication when the vehicles are otherwise mechanically coupled together.
2. State of the Art
U.S. Pat. No. 3,869,352, discloses a system to reduce the release of polluting emissions when coke is discharged or "pushed" from coking ovens. The system according to that patent comprises two railroad vehicles which are mechanically coupled together. The first vehicle, which is a hooded car, is adapted to directly receive a "push" of coke from a coking oven. The second vehicle, which contains gas cleaning equipment, is connected by a duct to receive gaseous emissions from the coke in the first vehicle.
In a two-vehicle system such as the one described in the aforementioned patent, the duct through which the gaseous emissions are conveyed between the vehicles is a vital element. The duct must be able to withstand severe, though limited bending as a result of the motion of the vehicles relative to one another. Further the duct must be able to withstand, without leakage, the high temperature and abrasive character of the emissions carried through it.
In prior two-vehicle systems, it is known to provide a rigid, continuous duct which is pivotably mounted to one of the vehicles. For example, it is known to provide a rigid duct whose one end is rigidly fixed to the first railroad vehicle and whose other end is pivotably fixed to the second vehicle in a manner similar to a ball and socket joint. Such a joint, however, is difficult to seal so as to prevent leakage of gaseous emissions.